Hey Cocker Gurus
!
The last marker I bought before retiring the sport years ago was an Eclipse E-Blade Cocker (2005, I think). I'm getting back into it and have ordered a Pooty Luxe but won't get it for another couple weeks. In the meantime, I'm trying to still play but cannot, for the life of me, make this gun function properly.

TLDR - My cocker won't shoot over 100fps. There just isn't much air coming out of the bolt. Please help!

Long Version: I bought it and it worked well enough out of box. Honestly, my 2001 Impulse worked better... I put a few upgrades on it (new bolt, new cocking rod chamber thingy in the front, those pro-series exhaust boxes) and the more I used it, the more finicky it became. Eventually, I'd walk onto the field unable to get it to shoot higher than 250fps or so. Eventually, I got so frustrated with the marker, that it was one of the reasons I quit paintball. I was fruitlessly screwing with the gun more than I was playing. I put it away for 7-8 years and didn't touch it once.
Fast-forward 7-8 years and I take it out, gas it up and it shoots ropes. On chrono it was in the low 280s and consistent. I went to play paintball a week later (hadn't adjusted the marker at all) and now I can't get it to shoot any faster than me actually throwing the paintball with my hand.
I've turned the reg up. I've turned it down. I've messed with the LPR. I've taken it entirely apart and cleaned it. I don't know what else to do. There just isn't enough air coming out of the bolt. I can stick my finger down the barrel and fire and it doesn't hurt! Strangely, there is a LOT of air coming out of the exhaust boxes on the cocking rod housing in the front. Sorry, I don't know what these parts are called. I'm going to sell it once the Luxe arrives but I'd like to have it working for whoever buys it. Any help is appreciated!